The present disclosure relates generally to methods of forming a nano-structure.
Porous anodic oxide structures may be used in a variety of applications including, but not limited to, micro- and nano-electronics (such as, e.g., in planarized aluminum interconnections, precision thin-film resistors, thin-film capacitors, and nano-structured field-emission cathodes), electrostatic and thermo-activated switching devices, LC high-frequency oscillators, AC amplifiers, triggers and other logic vacuum integrated circuits (VICs), gas micro- and nano-sensors, micro- and nano-channel plates, mesoscopic engines, wavelength-sensitive filters, reflective and absorbing surfaces, membranes, nozzles, precision apertures, and/or like. These anodic oxide structures may also include one or more arrays of nano-pores that are used, for example, to form nano-structures having one or more arrays of nano-pillars formed on and supported by a substrate. Fabrication processes for forming these nano-structures often dictate, at least in part, the geometry and/or chemistry of the individual nano-pillars, as well as the population density of arrays of the nano-pillars in the structure. Typically, each nano-pillar has a cylindrical-shaped portion at one end thereof, and a cone-shaped portion at another end thereof. The inconsistent shape along the length of the individual nano-pillars may, in some instances, hinder the formation of a substantially uniform nano-structure.